X-ray imaging apparatuses are apparatuses that are capable of obtaining an image inside an object by radiating X-rays onto the object and using the X-rays transmitted by the object. Since transmittance of X-rays varies according to the characteristics of a material used to form the object, an internal structure of the object can be imaged by detecting an intensity or strength of the X-rays transmitted by the object.
In detail, when an X-ray generation unit generates X-rays and radiates the X-rays onto the object, an X-ray detection unit detects the X-rays transmitted by the object and converts the detected X-rays into electrical signals. Conversion into the electrical signals is performed in units of pixels, one X-ray image can be obtained by combining an electrical signal corresponding to each pixel.
As a part of the X-ray image, a digital subtraction angiography (DSA) image for a dynamic organ is mainly used. In a method of extracting blood vessels from an angiography image according to the related art, the quality of the image is remarkably lowered, and a severe change of lighting occurs when the X-ray image is obtained. When the DSA image is used, a blood vessel region can be prominently expressed in an image in which a motion artifact and contrast are severe such that these problems can be solved.